Inkjet goes 3D

January 28/February 4, 2004

Just as color printers are becoming status quo, a new
technology may enable something more -- three-dimensional desktop printers.

Three-dimensional printers use high-intensity lasers to harden
extremely thin layers of liquid plastic or melt and fuse metal or plastic
powders to build up three-dimensional forms, and are used in industry
for both rapid prototyping and manufacturing. Lasers are relatively expensive
components, however.

Researchers from the University of Southern California have fashioned
a printer that makes three-dimensional forms without the use of a laser.

Instead of using a laser beam to selectively melt material, the
researchers' selective inhibition sintering method uses an inkjet nozzle
to treat portions of a powder with an anti-sintering agent like saltwater
so that it resists melting, then exposes the entire form to high-intensity
heat.

The selective inhibition sintering method is faster than laser
methods, uses less energy, and uses much cheaper components, according
to the researchers.

The researchers used their prototype 3D printer to build forms
using layers one-tenth of a millimeter thick. Each layer can be completed
in as few as 15 seconds. The prototype is accurate to within two-tenths
of a millimeter, and could be improved using a commercial quality printhead,
according to the researchers.

The technology has been licensed to build a commercial machine,
and could be used practically within a year, according to the researchers.
The work appeared in Issue 1, 2003 of Rapid Prototyping Journal.